Electron gain enthalpy of the atom - if im not wrong
Answer: -
¹⁰B has the same number of neutrons as ⁹Be
Explanation: -
Mass number of ⁹Be = 9
Atomic number of ⁹Be = 4
Number of neutrons of ⁹Be = mass number - atomic number
= 9 - 4 = 5
Mass number of ¹⁰B = 10
Atomic number of ¹⁰B= 5
Number of neutrons of ¹⁰B= mass number - atomic number
=10 - 5 = 5
Nucleus. Hope this helps!!
Carbon monoxide would be the anwser